Discolouration around exhaust

[Lesley Johnson]

In the last 2 months I've noticed that there is a build up of a black deposit on the car body above the exhaust tail pipe.
The car is 2 1/2 years old and has done 16,000 miles.
I took it to the local Porsche centre and they told me that it must have been caused by something I'd sprayed on it!? I haven't used any sprays on the car, so I think they are just trying to fob me off.
Has anyone else had this problem?

 

[Motorhead]

Lesley,

That doesn't look right to me. Have you started using or burning any oil recently?

I suggest that you wash and then clean the area with a reputable polish/cleaner and see if the deposit returns. If it does then take up the matter again with your PC although, unless you're covered by an extended warranty, they'll want to charge you for any investigations.

Jeff

 

[Lesley Johnson]

Thanks Jeff

I'm not sure about the oil, but I'll check.

The PC started cleaning it off, but they stopped and then told me that their warranty guy had had a look at it and said that it wouldn't be covered.

It it is still under warranty until end of September so I'll get back to them and ask them to investigate again.

Its getting valeted tomorrow so I'll ask if they can have a go at trying to remove it with a polish or cleaner

Thanks
Lesley

 

[BartyB]

Lesley, it looks like a carbon deposit (soot) to me which can only be a by-product of combustion, either caused by an over-rich mixture or burning oil. Any competent workshop should be able to analyse the exhaust gases for hydrocarbon content, as they have do for the MoT test. Burning oil seems unlikely given the car's mileage.

If you are using a lot of fuel, my money would be on a failed lambda sensor. If this is the case I would get this rectified as soon as possible so as to prevent damage to your catalytic converter. As both are parts of the exhaust system, neither would be covered by the warranty, so resolution could get expensive if left. Perhaps a visit to another PC would be the best way forward.

Alan

 

[Pete Ansbro]

Thanks Jeff

I'm not sure about the oil, but I'll check.

The PC started cleaning it off, but they stopped and then told me that their warranty guy had had a look at it and said that it wouldn't be covered.

It it is still under warranty until end of September so I'll get back to them and ask them to investigate again.

Its getting valeted tomorrow so I'll ask if they can have a go at trying to remove it with a polish or cleaner

Thanks
Lesley

You don't say how long you've owned the car?
I wonder what exactly the warranty guy* judged to NOT be covered under warranty - cleaning your back panel for you? You've not overfilled the engine oil? It'll be interesting to see what your valeter makes of it but today being the 13th of September and 17 days to go I'd be pressing very firmly for investigation/remedy under warranty. If it's around the exhaust logically it's either oil or petrol derived soot as has already been suggested.
*Warranty guy: I have a pal who worked freelance as a warranty guy for a large European car manufacturer. He was always very honest about earning his money by helping the dealership to avoid claims under warranty.
It sounds like you're being given the runaround: I hope I've misread your post. In this situation I think I'd be in there at first opportunity wearing my best business suit and prepared to kick up a fuss just when they're busy taking cars in at the start of the day.